8/11/2019 Natural Gas Pipe Sizing Section
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E.I
Piping
design sizing imperial
ote This informative
Annex
has
been
written in
normative
language to
facilitate adoption where users of
the
Code or
regulatory
authorities
wish
to
adopt it formally as additional
requirements
to this
Code
E.I.4
Multipliers to be used when the relative density of the gas is
other than 0.60
shall be as given
in
Table
A.15.
Canadian Standards Association
749 7 70
E.I.I
The required minimum size of Schedule
40
iron pipe shall
be determined
for
each
section
and each
outlet
of
th e
piping system shown
in
Figure E.1 . The
gas
has a relative density of 0.60
and
a heating value of
1000 Btu/ft
3
in the example shown in Figure E.1 .
In the example, the gas pressure in the section X A
is
2 psig, and the gas pressure from A
to
all ppli n es
is less
than
14 in
W e
Annex E informative
Example ofpiping design sizing imperial
and
metric
E.I.2
The pipe size for the sections from A
to
all ppli n e outlets shall be determined.
The distance between the last stage regul torA and the farthest ppli n e Eshall be established in
th e example shown in Figure E.1, it is 50 ft) to
determine the
longest run of th e system operating under
th e pressure of 14 in
W e
This distance shall t hen be used to size the entire system downstream of the
regul tor A. The choice of tables for a specific application shall be determined by the pressure supplied to
th e system
and
the pressure
drop
allowed.
Using the
50
ft line of Table A.2 imperial), the pipe sizes shall
be
as follows:
a) D-E for
60 000
Btuh requires an
NPS 1/2;
b) D-F for
25 000
Btuh requires an
NPS 1/2;
c)
C-G
for
150 000
Btuh requires an
NPS 3/4;
d)
B H
for
40000
Btuh requires an
NPS 1/2;
e)
C-D
for
85 000
Btuh requires an
NPS
1/2;
f) B-C for 235 000 Btuh requires an NPS 1; and
g) A-B for 275
000
Btuh requires an NPS 1.
E.I.3
The pipe size for t he 90 ft section X A operating at 2 psig using Table A.3 imperial) for 275 000 Btuh shall
be determined.
An
NPS 1/2 pipe shall
be
required.
236
January
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Service regulator and
meter
t
System regulator
Note: The example shown is of a general nature and does not
necessarily
include the allowances that
shall be
taken into
account in each particular installation
In every
installation all pertinent requirements in Clause 6 shall be adhered to
9
ft 20 ft 10ft C 10ft
~ 7 7 / r 4 4 ~ 4
D
B
V1
Canadian Standards Association
System operating at 2
psig
X
Natural
gas
andpropane
installation code
System operating at less than 1/2
psig
40000
Btuh
H
60000
Btuh
E
.t: F
V1
25000 Btuh
G
150000 Btuh
Figure E.I
Example
of
pipe design. sizing imperial
See Clauses E.1.1
an d
E.1.2.
E 2
Piping
design
sizing
metric
E 2
The required minimum size of Schedule 40 iron pipe shall be determined for each outlet of th e piping
system
shown
in Figure E 2 The gas has a relative density of
0.60
and a heating value of 38 MJ/m
3
in
the
example shown
in Figure E 2
In th e example, th e gas pressure in th e section X A is 14 kPa, and th e gas pressure from A
to
all
ppli nces is less than 3.5
kPa
E 2 2
The pipe size for th e sections from A to
all
ppli nce outlets shall be determined.
The distance
between
the last
stage regul tor
A
and
the farthest
ppl nce
Eshall be established
in the example, it is 15 m to determine th e longest run of th e system operating under th e pressure of
3.5
kPa
This distance shall
then
be used to size the entire system downstream of the regul tor
A
The
choice of tables for a specific application shall
be determined
by
th e
pressure supplied
to
the system
and
th e pressure
drop
allowed.
Using the 15m line of Table A.2 metric , the pipe sizes shall be as follows:
a D-E for
17.5
kW requires
an
NPS
1/2;
b D-F for 7.0
kW
requires an NPS 1/2;
c C-G for 45.0 kW requires an NPS 3/4;
January
1
37
8/11/2019 Natural Gas Pipe Sizing Section
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E.2.4
Multipliers to be used when the relative density of the gas is other than
0.60
shall be as given in
Table A.15.
E.2.3
The pipe size for
the 27
m section X A operating
at
14
kPa
using Table A.3 metric) for
81.5
kW shall
be
determined.
An
NPS
1/2 pipe shall
be
required.
Service regulator
andmeter
t System regulator
Note: The example shown is of a general nature and does not necessarily include the allowances that shall be taken into
account in each
particular
installation every
installation
all pertinent requirements
in Clause
6 shall be adhered
to
17.5 kW
E
Canadian Standards Association
E
12 kW
H
System operating at less than 3.5
kPa
Figure
E
Example of pipe design sizing metric
See Clause E.2.1.)
System operating at 14 kPa
E
7 m
6m
3m
C
3m
B
E
:
E
F
:
f
7.0kW
G
45
kW
8749 7 70
d)
B H
for
12.0
kW requires an
NP
1/2;
e)
C D
for 24.5
kW
requires an NP 1/2;
f) B-C for 69.5 kW requires an
NPS
1; and
g) A B for 81.5 kW requires an NPS 1.
8
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G 1
ote
This Annex is not a mandatory part of this Code,
nnex
F informative
uggested
gener l dimensions
for
dr ft hoods
Canadian Standards Association
Natural
gas and propane installation code
D
I
A ~ I
~
K
january 7
A
1 1
I ~
igure
l
Suggested general dimensions for a vertical draft hood
Continued
9
8/11/2019 Natural Gas Pipe Sizing Section
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N
l;J)
-
.I>.
0
Dimensions, in
mm )
:
-
-
C
D E F G H I
J
K L M
0
3 75
5.5 140 7.0 178 3.8 97 0.7 18 4.4 112 3.0 76
1.5 38 2.5 64
0.7
18
1.5 38 2.3 58
4 100
7.2 183 9.5 241 5.0 127
1.0
25 6.0 152
4.0
102 2.0 51)
3.5 89
1.0
25
2.0
51 3.0 76
5 125
9.4 240 10.8 274 5.3 135 1.5 38 8.0 203 5.0 127 2.3 58 4.0 102 0.9 23
2.4 61 3.5 89
6 150
11.5 292 12.0 305 5.6 142 1.9 48) 9.8 249 6.0 152 2.5 64 4.5 114 0.8 20
2.7
69 4.0 102
7 175 13.5 343
13.9 353
6.4 163 2.3 58 11.6 295 7.0 178 2.9 74 5.3 135
0.9
23
3.1
79 4.6
117
8 200 15.5 394 15.8 401
7.1
180
2.7
69 13.4 340 8.0 203 3.2 81 6.0 152
1.0
25 3.5 89 5.3 135
9 225 17.4 444 17.5 444 7.7 196 3.1 79
15.2 386 9.0 229 3.5 89 6.7 170 1.0 25
4.0
102 5.8 147
10 250) 19.7
500 18.8 478
7.9 201
3.6 91
17.2 437 10.0 254 3.8 96 7.3 185
1.0
25
4.3
109 6.2 157
11
275 22.2
564 20.7 526
8.4 213
4.3
109 19.6 498 11.0 279 4.1 104 8.0 203 1.5 38
4.6 117 6.6 168
12
300 24.7 627 22.2 564 8.7 221 5.0 127
22.0
559 12.0 305
4.4
112 8.5 216
1.7
43 5.0 127 7.0 178
ote Figure 1 illustrates only one design of a vertical draft hood and is not to be construed as the only design that maybe used hood of any other design
that
meets the requirements
of CS CANl 6 2 is
acceptable
Figure
F. l
Concluded
I::
N
o
-
@
b
::J
Q
::J
Q
::J
2-
i
o
g
::J
8/11/2019 Natural Gas Pipe Sizing Section
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Natural
gas and propane installation
code
I
I I I
1--
C
to I
I
F / l ~ /
1
M
I
r
j
i
H
t------ot
1---------1
A
- - - - - - ~ ? ~ - - - - r :
; 1
-
J-----
E
:r--j----;
Baffle
strap
Relief opening
Dimensions,
i n m m)
A
C D
E F G H
3 75) 6 150)
1-1/ 2 38)
4-3/4 121)
3-3/4
95) 1-3/8 35)
2-1/2 64)
4 100) 8 200)
2 50) 4-3/4 121) 5 125) 1-7/8 48)
3-3/8 86)
5 125) 10 250)
2-1/2 64) 4-3/4 121)
6-1/4 159)
2-3/8 60)
4-3 /1 6 106)
6 150) 12 300) 3 75)
4-3/4 121) 7-1/ 2 190) 2-7/8 73) 5 125)
7 175)
14 350) 3-1/ 2 89) 4-3/4 121) 8-3/4 222) 3-3/8 86) 5-7/8 149)
8 200) 16 400) 4 100)
4-3/4 121)
10 250)
3-7/8 98)
6- /16 1 70)
9 225) 18 450)
4-1/2 1 14)
4-3/4 121) 11-
1/ 4
286) 4-3/8 111)
7 1/ 2 190)
10 250) 20 500) 5 125) 4-3/4 121)
12 -
1/ 2 318) 4-7/8 124)
8-3/8 213)
275)
22 550)
5-1/2 140)
4-3/4 121) 13-3/4 349)
5-3/8
136)
9-3/16 233)
12 300) 24 600) 6 150) 4-3/4 121)
15 381)
5-7/8 149) 10 250)
J
K
L M
2-1/ 2 64) 2-1/2 64) 2-1/ 8 54) 9/16 14)
1-3/4 44)
3-3/8 86) 3-3/8 86)
2-7/8
73) 3/ 4 19)
2-5/16 59)
4-3/16 106) 4-3/16 106) 3-1/ 2 89) 15/16 24)
2-15/16 75)
5 125) 5 125) 4-1/4 108) 1-1/ 8 29)
3-
1/ 2
89)
5-7/8 149) 5-7/8 149) 5 125) 1-5/16 33)
4-1/16 102)
6-11/16
1 70)
6-11/1 6 1 70) 5-5/8 143) 1-
1/ 2
38)
4- /1 6 9)
7-1/2 190) 7-1/2 190)
6-3/8
162)
1-11/16 43) 5-1/ 4 133)
8-3/8 213)
8-3/8
213)
7 175)
1-7/8
48) 5-1 3/16 148)
9-3/16 233) 9-3/16 233)
7-3/4
197) 2-1/16 57)
6-3/8 162)
10 250) 10 250)
8-1/ 2 216)
2-1/4 57)
7 175)
Canadian Standards ssociation
Note:
Figure
F
illustrates only one design
of
a horizontal
draft hood
and
is
not
to
be
construed as the only design
that
may be
used
A
hood
of
any other design that meets the requirements
of
CSA CANl 6 2 is acceptable
igure F
uggested
general dimensions for
a
horizontal draft hood
January 2010
4
8/11/2019 Natural Gas Pipe Sizing Section
7/12
8/11/2019 Natural Gas Pipe Sizing Section
8/12
Note: This informative nnex
has been written in
normative language
to facilitate adoption
where users of
the
Code
or
regulatory authorities wish to adopt it formally as additional requirements to
this
Code
Canadian
Standards
ssociation
Annex informative
iping
exp nsion nd
flexibility
Natural gas
and propane
installation code
G I General
Problems are
not
usually experienced
in
residential piping systems with thermal expansion because
th e piping is relatively short.
owever in commerci l and industri l buildings there can be substantial variations in th e lengths of
gas piping mains as
the
indoor temperature changes
on
weekends
or
between seasons.
It
is therefore
essential
that
provisions be made in the piping design for flexibility to avoid undesirable bending
and
strong forces
at
elbows
or
joints.
This flexibility is obtained by
the
use of designed pipe bends, loops, offsets, expansion, hints, or swivel
joints.
The
piping shall
be
anchored
at appropriate
locations
to
control
the
direction of expansion
and
contraction.
G
Gas piping
to rooftop units
Due to
the
wide range of
temperatures on
a roof between
summer
and winter, piping design shall provide
for expansion and contraction. Because of
the
exposure
to
sunlight and rain or snow, coated or wrapped
gas piping is
not recommended
Bare steel piping
and fittings
shall
be
cleaned after assembly,
painted
with a metal primer, and given at least one coat of exterior enamel paint.
Expansion control loops should be used
on
pipe sizes of 2
in
50 mm
or
less
whenever the
unrestrained
pipe length is
at
least 100 ft 30 m . Larger diameter piping is generally installed with expansion joints.
As shown in
Figure G.1,
the
control loop consists of 90 offsets to
th e
main pipe run so it provides
an
open ended box configuration.
For purposes of design, a 90
change
of direction or an offset may be considered the equivalent to a
control loop when
the
offset length is
at
least three times Dimension A in Figure G.1.
Some
form of thermal expansion control shall
be
provided for each
100
ft 30 m . For example, a
200
ft
61
m length shall be anchored
in the
centre between each loop. The anchor of an offset
or
90
bend
should be
not
closer than 10ft 3 m from
the bend to
permit expansion.
Suitable pipe supports are commercially available to permit th e free movement of piping when it
expands and contracts.
January 20 70 43
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8749 7 70
44
Wall thickness
Schedule
40 ,
I ron pipe size, in in mm
3/4 0.11 3 2.87
1 0.133 3.38
1-1/4 0.140
3.56
2
1.154
29.31
Figure G l
Expansion
control loop
See Clause G.2.
anadian
Standards
ssociation
Dimension
ft
m)
4.5 1.4
5.0 1.5
5.5 1.6
6.5 2.0
January 2070
8/11/2019 Natural Gas Pipe Sizing Section
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Annex H normative
urging ofpiping nd
tubing
systems where
re dily ccessible
burner
is
not v il ble or
where n ppli nce
is
not
equipped
with
continuous pilot
Canadian Standards ssociation
Natural gas
and
propane installation code
Note: This
nnex
is
amandatory part of
this
Code
H I
Purging of piping and tubing systems where a
re dily ccessible burner is
not available or where an
appliance
is
not equipped with a continuous pilot shall be undertaken as outlined in Clauses
H 2
to H.7.
H
The procedure shall
be
applicable to
the
purging of air
or
inert gas using natural gas from a piping/tubing
system downstream of th e meter.
H 3
No smoking shall be permitted
when
purging.
H 4
Prior
to commencing
th e purge all sources, or potential sources, of ignition shall be removed or shut off.
H S
The purging procedure shall be used only under the following conditions:
a maximum piping system size is
NPS
1;
b maximum tubing size
is NTS
3/4;
c maximum piping or tubing system gas pressure
is
2 psig 14 kPa ;
d maximum gas pressure at purging point is in w.e. 2.74 kPa or less; and
e
the
longest run of pipe
or
tubing
in
th e system
is
ft 30 m or less.
H 6
Piping
and
tubing systems not meeting th e conditions listed
in
Clause
H 5
shall be
purged
to the
outdoors. Those that do meet these conditions shall be purged in accordance with Clause H.7.
H 7
The purging procedure shall be as follows:
a Use only the
pproved purging assembly. See Figure H.1.
b Inspect
the
purging assembly prior to use. Replace worn or
damaged
hose and ensure that all joints
are tight.
January 2070 45
8/11/2019 Natural Gas Pipe Sizing Section
11/12
Table
H.l
Approximate
purging t imes
a t
7 in
w.e . 1 .74
kPa)
See Clause
H.7.
c Ensure that the manual shut-off valve for
the
appliance
is
closed.
d Connect the purging assembly to the appliance dirt pocket where so equipped, or to th e
appliance
piping, as close to
the appliance
as is practicable.
e Ensure that no sources of ignition are present within th e purge area and that the purge area
is
well
ventilated.
f) Determine th e approximate purging time from Table H.l . Ensure that
the
purge does
no t
exceed
100
s.
g Open
th e
manual shut-off
valve
for
the appliance.
h Begin purging by fully opening the automatic shut-off release purging valve
on
the
purging
assembly. Purge in a continuous and uninterrupted manner. Caution: Under no circumstances shall
the automatic shut-off
release
purging
valve
be fixed
in
the open position.
i) Terminate purging when
the
smell of gas
is detected
a t the purging valve outlet or when th e
approximate
purging time has
been
reached. Do
not
exceed
the
purging time by more
t han lOs .
U When purging is terminated, close the manual shut-off valve and disconnect the purging assembly
from th e piping system.
k)
Reassemble
th e appliance
piping,
open the
manual shut-off
valve
and soap test the affected joints
to ensure that
there
are no leaks.
8749.7 70
246
Pipe/tubing size,
in
NPS
1/2
NPS
1
NTS
1/2
NTS
3/4
Canadian Standards ssociation
Length
of pipe/tubing,
Time
to purge,
f t
m) s
10
3 3
20 6 5
60 18 15
100
30 26
10 3) 7
20 6 14
60 18 43
100
30
84
10
3 1
20 6 2
60 18 6
100 30 10
10 3) 3
20 6 5
60 18 15
100
30 26
January 20
7
a
8/11/2019 Natural Gas Pipe Sizing Section
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anadian
Standards
ssociation
To be
connected to
appliance piping at
dirt pocket
or
as
close
t o t he
appliance
as practicable
NPS
3/4
x NPS
1/2
coupling
Natural gas
and propane
installation
code
Standard tip
NPS 1/4 purging
valve foster
model BG-2l
automatic shut-off
release)
NPS 1/2 Type 1
flexible hose
24 in 600 mm) long)
january 7
Figure
H l
Approved
purging
assembly
See Clause H.7.)
47